I've beaten 3 mavericks and so far, amazing game, the challenge seems very fair and the difficulty is very close to the SNES Megaman X games.
Although some level design seems to lean too much on "Platforms over Instakill/Bottomless pits, go!" at certain points in the level and contains quite a bit of obscured by camera instakills, it's nothing that a calm approach can't handle, which is good!
The only thing I think the game needs more is check points...
Arson Vulpine's Stage has this loooooong crushing portion that goes for probably over half of the stage, and while it's not that bad, one mistake can lead to basically back to the start of the level and it can be a bit frustrating, especially considering Megaman X's explorative nature. How can I explore and find secrets if everytime I die I'm sent back 2~3 set pieces?
Tundrion Bear Stage is another example, we have that quite long icicle segment where we need to shoot the ice from the ceiling to make platforms over spikes, it takes a while and if ends with a bottomless pit segment. You'd think the end of that set piece(when you get outside) would have a checkpoint, so I decided to jump on the pits and explore for secrets like any sane person would do(lol) and I accidentally ended up dying... and then I had to do the ceiling ice platform segment again like, c'mon...
Again, it's not unbalanced difficulty like most Fan Games have(which is great!), it's just a lack of check points after what feels long set pieces that this game needs imo.